Postlingual deafness in Eveno-Bytantaysky National District of the Sakha Republic (Yakutia): audiological and clinical-genealogical analysis

In this paper we present for the first time the results of the audiological and clinical-genealogical research of the population of settlements Batagai-Alyta and Kustur of the Eveno-Bytantaisky National District (ulus) of the Sakha Republic (Yakutia) for studying the postlingual form of deafness of unknown etiology, which we for the first time have identified earlier in 3 Evens. As a result of an audiological examination of 72 people, 10 patients from 6 nuclear families who met the criteria of postlingual form of hearing loss were found. The segregation analysis carried out in these families confirmed the autosomal recessive type of inheritance of this form of postlingual hearing loss. The distant relationship of the examined patients with postlingual hearing loss living in two villages of the Eveno-Bytantaisky National District of the Sakha Republic can indicate to the role of the founder effect in the local prevalence of this pathology. The results of present study and obtained expedition material will be the basis for further research of the molecular genetic etiology of this form of deafness and the discovering of mechanisms of its accumulation in this region of Yakutia.

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